From: Kent Overstreet <kent.overstreet@linux.dev>
Date: Wed, 20 Sep 2023 05:19:53 +0000 (-0400)
Subject: bcachefs: Fix strndup_user() error checking
X-Git-Tag: v6.7-rc1~201^2~37
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=97ecc23632fad75c43809b3f5010800289884a08;p=thirdparty%2Fkernel%2Flinux.git

bcachefs: Fix strndup_user() error checking

strndup_user() returns an error pointer, not NULL.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
---

diff --git a/fs/bcachefs/chardev.c b/fs/bcachefs/chardev.c
index e8b6733e7f716..f69e15dc699c9 100644
--- a/fs/bcachefs/chardev.c
+++ b/fs/bcachefs/chardev.c
@@ -86,10 +86,9 @@ static long bch2_ioctl_assemble(struct bch_ioctl_assemble __user *user_arg)
 		devs[i] = strndup_user((const char __user *)(unsigned long)
 				       user_devs[i],
 				       PATH_MAX);
-		if (!devs[i]) {
-			ret = -ENOMEM;
+		ret= PTR_ERR_OR_ZERO(devs[i]);
+		if (ret)
 			goto err;
-		}
 	}
 
 	c = bch2_fs_open(devs, arg.nr_devs, bch2_opts_empty());
@@ -117,8 +116,9 @@ static long bch2_ioctl_incremental(struct bch_ioctl_incremental __user *user_arg
 		return -EINVAL;
 
 	path = strndup_user((const char __user *)(unsigned long) arg.dev, PATH_MAX);
-	if (!path)
-		return -ENOMEM;
+	ret = PTR_ERR_OR_ZERO(path);
+	if (ret)
+		return ret;
 
 	err = bch2_fs_open_incremental(path);
 	kfree(path);
@@ -189,8 +189,9 @@ static long bch2_ioctl_disk_add(struct bch_fs *c, struct bch_ioctl_disk arg)
 		return -EINVAL;
 
 	path = strndup_user((const char __user *)(unsigned long) arg.dev, PATH_MAX);
-	if (!path)
-		return -ENOMEM;
+	ret = PTR_ERR_OR_ZERO(path);
+	if (ret)
+		return ret;
 
 	ret = bch2_dev_add(c, path);
 	kfree(path);
@@ -231,8 +232,9 @@ static long bch2_ioctl_disk_online(struct bch_fs *c, struct bch_ioctl_disk arg)
 		return -EINVAL;
 
 	path = strndup_user((const char __user *)(unsigned long) arg.dev, PATH_MAX);
-	if (!path)
-		return -ENOMEM;
+	ret = PTR_ERR_OR_ZERO(path);
+	if (ret)
+		return ret;
 
 	ret = bch2_dev_online(c, path);
 	kfree(path);